<!DOCTYPE html>
<html>
	<head>
		<title>使用threejs创建几何体添加坐标轴材质阴影动画</title>
		<script type="text/javascript" src="libs/three.js"></script>
		<script type="text/javascript" src="libs/dat.gui.js"></script>
		<script type="text/javascript" src="libs/OrbitControls.js"></script>
		<style>
			body {
				margin: 0;
				overflow: hidden;
			}
		</style>
	</head>
	<body>
		<div id="dom"></div>
		<script type="text/javascript">
			var camera;
			var renderer;
			function init() {
				// 创建一个场景，它将包含我们所有的元素，如物体，相机和灯光。
				var scene = new THREE.Scene();

				// 创建一个摄像机，它定义了我们正在看的地方
				camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
				// 将摄像机对准场景的中心
				camera.position.x = 10;
				camera.position.y = 50;
				camera.position.z = 90;
				camera.lookAt(scene.position);
				var orbit = new THREE.OrbitControls(camera);

				// 创建一个渲染器并设置大小，WebGLRenderer将会使用电脑显卡来渲染场景
				renderer = new THREE.WebGLRenderer();
				renderer.setClearColor(new THREE.Color("#0e0934"));
				renderer.setSize(window.innerWidth, window.innerHeight);
				// 设置渲染器需要阴影效果
				renderer.shadowMapEnabled = true;

				// 在屏幕上显示坐标轴
				var axes = new THREE.AxisHelper(100);
				scene.add(axes);

				// 将平面添加到场景中
				var plane = createPlaneGeometryBasicMaterial();
				scene.add(plane);

				// 将立方体添加到场景中
				var cube = createBoxGeometryLambertMaterial();
				scene.add(cube);

				// 将球体添加到场景中
				var sphere = createSphereGeometryLambertMaterial();
				scene.add(sphere);
				
				// 为阴影添加光源
				var spotLight = new THREE.SpotLight(0xffffff);
				spotLight.position.set(-40, 60, -10);
				// 设置产生阴影的光源
				spotLight.castShadow = true;
				spotLight.shadowCameraVisible = true;
				scene.add(spotLight);

				// 将呈现器的输出添加到HTML元素
				document.getElementById("dom").appendChild(renderer.domElement);
				
				// 使用GUI调试库
				var controls = new function () {
					// 设置初始值
				    this.rotationSpeed = 0.02;
				    this.bouncingSpeed = 0.03;
					this.numberOfObjects = scene.children.length;
					// 随机生成一个立方体
					this.addCube = function () {
					    // 将立方体添加到场景中
					    scene.add(createBoxGeometryLambertMaterialRandom());
						// 更新界面中的对象数量
					    this.numberOfObjects = scene.children.length;
					};
					
					// 移除场景中的对象，移除添加到场景中的最后一个对象
					this.removeCube = function () {
						// 获取场景中的所有对象
						var allChildren = scene.children;
						var lastObject = allChildren[allChildren.length - 1];
						// 只移除THREE.Mesh对象
						if (lastObject instanceof THREE.Mesh && lastObject != plane && lastObject != cube && lastObject != sphere) {
							scene.remove(lastObject);
							// 更新界面中的对象数量
							this.numberOfObjects = scene.children.length;
						}
					};
					
					// 打印场景中的所有对象
					this.outputObjects = function () {
						console.log(scene.children);
					}
				};
				var gui = new dat.GUI();
				// 设置两个变量的取值范围
				gui.add(controls, 'rotationSpeed', 0, 0.5);
				gui.add(controls, 'bouncingSpeed', 0, 0.5);
				// 添加事件
				gui.add(controls, 'addCube');
				gui.add(controls, 'removeCube');
				gui.add(controls, 'outputObjects');
				// 监听变量
				gui.add(controls, 'numberOfObjects').listen();
				
				// 启动动画
				renderScene();
				
				// 创建一个随机大小颜色的立方体
				function createBoxGeometryLambertMaterialRandom() {
					var cubeSize = Math.ceil((Math.random() * 3));
					// 创建一个立方体并设置大小
					var cubeGeometry = new THREE.BoxGeometry(cubeSize, cubeSize, cubeSize);
					// MeshLambertMaterial设置材质
					var cubeMaterial = new THREE.MeshLambertMaterial({color: Math.random() * 0xffffff});
					var cube = new THREE.Mesh(cubeGeometry, cubeMaterial);
					// 设置该物体投射阴影
					cube.castShadow = true;
					// 设置该立方体的名称
					cube.name = "cube-" + scene.children.length;
					// 设置立方体位置
					cube.position.x = -30 + Math.round((Math.random() * 60));
					cube.position.y = Math.round((Math.random() * 5));
					cube.position.z = -20 + Math.round((Math.random() * 20));
					return cube;
				}
				// 创建一个MeshLambertMaterial材质的立方体
				function createBoxGeometryLambertMaterial() {
					// 创建一个立方体并设置大小
					var cubeGeometry = new THREE.BoxGeometry(4, 4, 4);
					// MeshLambertMaterial设置材质
					var cubeMaterial = new THREE.MeshLambertMaterial({color: 0xff0000});
					var cube = new THREE.Mesh(cubeGeometry, cubeMaterial);
					// 设置该物体投射阴影
					cube.castShadow = true;
					// 设置立方体位置
					cube.position.x = -4;
					cube.position.y = 3;
					cube.position.z = 0;
					return cube;
				}
				// 创建一个基础材质的立方体
				function createBoxGeometryBasicMaterial() {
					// 创建一个立方体并设置大小
					var cubeGeometry = new THREE.BoxGeometry(4, 4, 4);
					// MeshBasicMaterial（基础材质不会对光源有反应只会使用指定的颜色渲染）
					var cubeMaterial = new THREE.MeshBasicMaterial({
						color: 0xff0000,
						wireframe: true
					});
					var cube = new THREE.Mesh(cubeGeometry, cubeMaterial);
					// 设置立方体位置
					cube.position.x = -10;
					cube.position.y = 3;
					cube.position.z = 0;
					return cube;
				}
				// 创建一个平面
				function createPlaneGeometryBasicMaterial() {
					// 创建地平面并设置大小
					var planeGeometry = new THREE.PlaneGeometry(100, 70);
					var planeMaterial = new THREE.MeshBasicMaterial({
						color: 0xcccccc
					});
					var plane = new THREE.Mesh(planeGeometry, planeMaterial);
					// 设置接受阴影
					plane.receiveShadow = true;
			
					// 设置平面位置并旋转
					plane.rotation.x = -0.5 * Math.PI;
					plane.position.x = 0;
					plane.position.y = 0;
					plane.position.z = 0;
					return plane;
				}
				// 创建一个球形几何体
				function createSphereGeometryLambertMaterial() {
					// 创建一个球体
					var sphereGeometry = new THREE.SphereGeometry(4, 20, 20);
					// var sphereMaterial = new THREE.MeshBasicMaterial({
					// 	color: 0x7777ff,
					// 	wireframe: true
					// });
					var sphereMaterial = new THREE.MeshLambertMaterial({color: 0xff0000});
					var sphere = new THREE.Mesh(sphereGeometry, sphereMaterial);
					// 设置该物体投射阴影
					sphere.castShadow = true;
			
					// 位置范围
					sphere.position.x = 20;
					sphere.position.y = 4;
					sphere.position.z = 2;
					return sphere;
				}
				
				// 动画渲染
				var step = 0;
				function renderScene() {
					// 遍历场景中所有子对象
					scene.traverse(function (e) {
					    if (e instanceof THREE.Mesh && e != sphere && e != plane) {
							// 将立方体绕轴旋转
					        e.rotation.x += controls.rotationSpeed;
					        e.rotation.y += controls.rotationSpeed;
					        e.rotation.z += controls.rotationSpeed;
					    }
					});
					
					orbit.update();
				    // 将立方体绕轴旋转
					cube.rotation.x += controls.rotationSpeed;
					cube.rotation.y += controls.rotationSpeed;
					cube.rotation.z += controls.rotationSpeed;
				
				    // 将球上下弹起
				    step += controls.bouncingSpeed;
				    sphere.position.x = 20 + ( 10 * (Math.cos(step)));
				    sphere.position.y = 2 + ( 10 * Math.abs(Math.sin(step)));
				
				    // 使用requestAnimationFrame函数进行渲染
				    requestAnimationFrame(renderScene);
				    renderer.render(scene, camera);
				}

				// 渲染的场景
				renderer.render(scene, camera);
			}
			window.onload = init;
			
			function onResize() {
			    camera.aspect = window.innerWidth / window.innerHeight;
			    camera.updateProjectionMatrix();
			    renderer.setSize(window.innerWidth, window.innerHeight);
			}
			// 监听调整大小事件
			window.addEventListener('resize', onResize, false);
		</script>
	</body>
</html>
